David Letterman’s visit to Birmingham this past weekend not only included a sold-out concert by Jason Isbell and the 400 Unit at WorkPlay Theatre, but also a hush-hush dinner for about 70 guests at Highlands Bar and Grill.

Isbell and the 400 Unit’s Saturday night concert was a benefit for Habitat, which helps build affordable housing for families in need.

“Late Show” band leader Paul Shaffer joined Isbell and the band to perform a set of cover songs, and while onstage, Shaffer acknowledged Letterman sitting in the WorkPlay balcony.

Letterman and Shaffer talked about their visit to Birmingham on “Late Show” Monday.

“Paul and I had the good fortune to be in Birmingham, Ala., last week, and Paul and Jason Isbell and the 400 Unit appeared live onstage at a place called the WorkPlay,” Letterman said.

“What a tremendous night, and I want to thank you (Shaffer) and everybody in Birmingham, Ala.,” he added.

Before Saturday’s concert, Letterman hosted about 70 friends and supporters of Habitat for Humanity at a private dinner that included braised oxtail and short ribs, triggerfish chowder and Highlands’ famous baked grits.

Letterman, who was making his first visit to the James Beard-nominated restaurant, was especially fond of the fried oysters, Highlands chef and owner Frank Stitt said.

“I don’t think I’ve ever seen anybody eat so many fried oysters and love ’em as much,” Stitt said. “He loved all of the food, and it was great having him here.”

Birmingham musician Mark Kimbrell and his band entertained Letterman and his dinner guests.

The entire restaurant was closed for Letterman’s visit, Stitt added.

“We had to keep it a secret,” Stitt said. “He seems like he enjoys not being in the spotlight when he does things like this.”